package org.simantics.maps.server.ui.prefs;

import java.io.IOException;
import java.net.URISyntaxException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.List;

import org.eclipse.core.runtime.preferences.InstanceScope;
import org.eclipse.jface.layout.GridDataFactory;
import org.eclipse.jface.layout.GridLayoutFactory;
import org.eclipse.jface.preference.BooleanFieldEditor;
import org.eclipse.jface.preference.ComboFieldEditor;
import org.eclipse.jface.preference.FieldEditorPreferencePage;
import org.eclipse.jface.preference.FileFieldEditor;
import org.eclipse.jface.preference.IPreferenceStore;
import org.eclipse.jface.preference.IntegerFieldEditor;
import org.eclipse.jface.util.IPropertyChangeListener;
import org.eclipse.jface.util.PropertyChangeEvent;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Group;
import org.eclipse.swt.widgets.Label;
import org.eclipse.ui.IWorkbench;
import org.eclipse.ui.IWorkbenchPreferencePage;
import org.eclipse.ui.preferences.ScopedPreferenceStore;
import org.simantics.district.maps.server.TileserverMapnik;
import org.simantics.district.maps.server.TileserverMapnikInstance;
import org.simantics.district.maps.server.prefs.MapsServerPreferences;
import org.simantics.maps.server.ui.TileserverMapnikStartJob;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class MapsServerPreferencePage extends FieldEditorPreferencePage implements IWorkbenchPreferencePage {

    private static final Logger LOGGER = LoggerFactory.getLogger(MapsServerPreferencePage.class);
    
    private TileserverMapnik server;

    private FileFieldEditor addNew;

    public MapsServerPreferencePage() {
        super(GRID);
        setDescription("Maps server preferences");
    }
    
    @Override
    public void init(IWorkbench workbench) {
        try {
            server = TileserverMapnikInstance.get();
        } catch (IOException | URISyntaxException e) {
            LOGGER.error("Could not initialize " + getClass(), e);
        }
    }

    @Override
    protected IPreferenceStore doGetPreferenceStore() {
        return new ScopedPreferenceStore(InstanceScope.INSTANCE, MapsServerPreferences.P_NODE);
    }

    private void createServerStatusField(Composite parent) {
        Label label = new Label(parent, SWT.NONE);

        Button b = new Button(parent, SWT.NONE);
        updateWidgets(label, b);
        b.addSelectionListener(new SelectionAdapter() {
            
            @Override
            public void widgetSelected(SelectionEvent e) {
                try {
                    if (server.isRunning()) {
                        server.stop();
                        updateWidgets(label, b);
                    } else {
                        new TileserverMapnikStartJob().schedule();
                    }
                } catch (Exception ex) {
                    LOGGER.error("Could not start/stop server", ex);
                }
            }
        });
    }
    
    private void updateWidgets(Label label, Button b) {
        String labelText = "";
        String buttonText = "";
        int labelColor = -1;
        try {
            if (server.isRunning()) {
                buttonText = "Stop";
                labelText = "running";
                labelColor = SWT.COLOR_DARK_GREEN;
            } else {
                labelText = "stopped";
                buttonText = "Start";
            }
        } catch (IOException | InterruptedException e) {
            LOGGER.error("Could not create server status field!", e);
            labelText = "unknown";
            labelColor = SWT.COLOR_DARK_RED;
        }
        label.setText("Tileserver is currently " + labelText);
        label.setForeground(getShell().getDisplay().getSystemColor(labelColor));
        
        b.setText(buttonText + " server");
    }
    
    private void createGeneralGroup() {
        Group serverGroup = new Group(getFieldEditorParent(), SWT.NONE);
        serverGroup.setText("General");
        GridDataFactory.fillDefaults().grab(true, false).span(2, 1).applyTo(serverGroup);
        
        createServerStatusField(serverGroup);

        IntegerFieldEditor port = new IntegerFieldEditor(MapsServerPreferences.P_DEFAULT_PORT, "Tileserver port", serverGroup);
        addField(port);

        BooleanFieldEditor automatically = new BooleanFieldEditor(MapsServerPreferences.P_START_AUTOMATICALLY, "Start tileserver automatically", serverGroup);
        addField(automatically);
        
        Button openInExplorer = new Button(serverGroup, SWT.NONE);
        openInExplorer.setText("Open server folder");
        openInExplorer.addSelectionListener(new SelectionAdapter() {
            
            @Override
            public void widgetSelected(SelectionEvent e) {
//                E4WorkbenchUtils.showInSystemExplorer("");
            }
        });
        
        GridLayoutFactory.fillDefaults().numColumns(2).equalWidth(false).extendedMargins(12, 12, 12, 12).spacing(5, 4).applyTo(serverGroup);
    }
    
    @Override
    protected void createFieldEditors() {
        createGeneralGroup();
        
        createStylesGroup();
        
        createTilesGroup();
    }

    private void createStylesGroup() {
        Group stylesGroup = new Group(getFieldEditorParent(), SWT.NONE);
        stylesGroup.setText("Styles");
        GridDataFactory.fillDefaults().grab(true, false).span(2, 1).applyTo(stylesGroup);
        
        createTM2StylesField(stylesGroup);
        
        GridLayoutFactory.fillDefaults().numColumns(2).equalWidth(false).extendedMargins(12, 12, 12, 12).spacing(5, 4).applyTo(stylesGroup);
    }
    
    private void createTM2StylesField(Composite parent) {
        try {
            List<String> styles = server.listStyles();
            
            String[][] namesAndValues = new String[styles.size()][];
            for (int i = 0; i < styles.size(); i++) {
                String style = styles.get(i);
                String[] nameAndValue = new String[2];
                nameAndValue[0] = style;
                nameAndValue[1] = style;
                namesAndValues[i] = nameAndValue;
            }
            
            ComboFieldEditor selector = new ComboFieldEditor(MapsServerPreferences.P_CURRENT_TM2STYLE, "Tile Styles", namesAndValues, parent);
            addField(selector);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    
    private void createTilesGroup() {
        Group tilesGroup = new Group(getFieldEditorParent(), SWT.NONE);
        tilesGroup.setText("MBTiles");
        GridDataFactory.fillDefaults().grab(true, false).span(2, 1).applyTo(tilesGroup);
        
        createTilesField(tilesGroup);
        
        GridLayoutFactory.fillDefaults().numColumns(3).equalWidth(false).extendedMargins(12, 12, 12, 12).spacing(5, 4).applyTo(tilesGroup);
    }

    private void createTilesField(Composite parent) {
        try {
            List<String> tiles = server.availableMBTiles();
            
            String[][] namesAndValues = new String[tiles.size()][];
            for (int i = 0; i < tiles.size(); i++) {
                String style = tiles.get(i);
                String[] nameAndValue = new String[2];
                nameAndValue[0] = style;
                nameAndValue[1] = style;
                namesAndValues[i] = nameAndValue;
            }
            
            ComboFieldEditor selector = new ComboFieldEditor(MapsServerPreferences.P_CURRENT_MBTILES, "MBTiles", namesAndValues, parent);
            addField(selector);
            
            addNew = new FileFieldEditor("Add new tiles", "Add new tiles", parent);
            addNew.setPropertyChangeListener(new IPropertyChangeListener() {
                
                @Override
                public void propertyChange(PropertyChangeEvent event) {
                    System.out.println(event);
                }
            });
            
        } catch (IOException e) {
            LOGGER.error("Could not create tiles field", e);
        }
    }
    
    @Override
    protected void performApply() {
        // Upload new mbtiles file
        String fileLocation = addNew.getStringValue();
        if (fileLocation != null && !fileLocation.isEmpty()) {
            Path p = Paths.get(fileLocation);
            Path target = server.getDataDirectory().resolve(p.getFileName());
            try {
                Files.copy(p, target);
            } catch (IOException e) {
                String message = "Could not upload " + fileLocation + " to " + target.toAbsolutePath(); 
                LOGGER.error(message, e);
                setErrorMessage(message);
            }
        }
        super.performApply();
    }
    
    @Override
    public boolean performOk() {
        boolean success = super.performOk();
        
        try {
            server.stop();
            new TileserverMapnikStartJob().schedule();
        } catch (Exception e) {
            LOGGER.error("Could not restart tileserver-mapnik", e);
        }
        
        return success;
    }

}